About 60 people gathered at the pop-up "refugee embassy" on a Canberra median strip during in peak hour.

ABC News: Tegan Osborne

A pop-up "refugee embassy" appeared outside a Department of Immigration office building Canberra on Tuesday amid a protest over the Australian Government's treatment of asylum seekers.

About 60 people gathered in peak hour traffic on a median strip along Benjamin Way at Belconnen, the first action in a "long campaign" against Immigration Minister Scott Morrison and his policies, they say.

Refugee Action Committee convenor John Minns said the idea of a refugee embassy was to highlight the absence of a diplomatic representation for asylum seekers and their right to protection.

This right, he said, was recognised by the international community in 1951, in the Convention relating to the Status of Refugees established after World War II.

Attendees at the peaceful rally waved signs demanding an end to offshore processing of asylum seekers and accusing Mr Morrison of having the blood on his hands.

"Its clear when both the Coalition and Labor agree on what's happening that the policy is not going to change in the short term," Mr Minns said.

"It's a question of building a movement in the long term, so this embassy is going to be popping up all over the place in Canberra."

Mr Minns said there were plans afoot to bring the pop-up embassy to The Lodge, Parliament House and a number of other locations in the not-too-distant future.

"You'll see a lot more of us; we've got a lot of places on our radar," he said.

Comment was being sought from Mr Morrison and the department.

Mr Minns stressed that Tuesday's protest was not against department employees, but against the policies they were implementing.

"We've had people from immigration approach us and say they feel ashamed of the policies that they're implementing, but there's nothing really that they can do about it," he said.

"We'd love them to come out and say what they think but realistically... their minister, Scott Morrison, has made it very clear that any slightest public dissent from his view will be severely punished."

Class action launched for Christmas Island asylum seekers

The protest came as a Melbourne law firm launched class action against Mr Morrison and the Immigration Department on behalf of a six-year-old girl held in detention on Christmas Island.